* subversion/libsvn_wc/wc-queries.sql
  (STMT_INSTALL_WORKING_NODE_FOR_DELETE): Make overwriting existing records
    an error (which would show a failure in svn_wc__db_extend_parent_delete)


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1539367 13f79535-47bb-0310-9956-ffa450edef68